[cfe-dev] [llvm-dev] Phabricator -> GitHub PRs?

[Hubert Tong via cfe-dev]

On Thu, Jan 16, 2020 at 1:30 PM David Greene via cfe-dev <
cfe-dev at lists.llvm.org> wrote:

> Joerg Sonnenberger via cfe-dev <cfe-dev at lists.llvm.org> writes:
>
> > One typical case for a patch series is if you need infrastructure in a
> > number of places in place first. Sending all changes at once allow
> > others to see where you are going, independent of whether the individual
> > pieces are acceptable immediately or not. Yes, this can mean later
> > patches need to be reworked for larger structural changes, but that
> > doesn't necessarily invalidate review remarks already made.
>
> I can certainly see the utility of this.  I've never tried it since
> posting patches via the web interface is not at all convenient and as
> I've mentioned before I can't get arcanist to work.  Does arcanist take
> care of organizing the series?
>
> How do reviews work?  Does each patch get a separate review page like
> any other patch?
>
> Let's say patch 3 in a series is approved and it could be committed
> without patches 1 and 2 (like Renato I question why this is a patch
> series if so, but let's assume it for argument's sake).  That means I
> need to rebase -i my branch in order to get patch 3 committed, right?
>
> Like Renato, I actually find that more burdensome than just putting
> patch 3 in its own branch in the first place and doing a separate review
> of it.  In other words, my definition of "patch series" is the same as
> Renato's: a linear series of commits each of which is dependent on the
> previous commits.  With that definition, "early approval" of later
> patches really doesn't help get things committed earlier.
>
> I definitely see the advantage of not invalidating existing review
> comments if the series is rebased/changed.  I confess I don't know how
> GitHub handles rebases (see my other post with questions about that).
>
> > The other case is reworking a pass to handle a couple of similar, but not
> > identical cases. It might not be possible to take out patch 2 in a
> > series in this case, but most often the review changes here are smaller
> > "stylistic" issues without huge impact on later steps.
>
> I'm sorry I don't really follow this.  How does it differ from the first
> case?  Are you saying you're grouping two similar but basically
> independent changes together?  I would think doing so violates the "one
> topic per review" principle (that's maybe not an LLVM policy per se,
> just the way I think to think about things).
>
I'm not sure what that the line on "basically independent" is
well-established, but sometimes syntactic merge conflicts on changes that
are related but not semantically ordered occur. For the purposes of
facilitating integration testing, allowing reviewers to reproduce a common
state of the code base, etc. it can be helpful to create a patch series in
Phabricator representing a local rebased linear history. Even if the
submitter has a good solution for merging the changes together whenever
they want to do integration testing, patches/PRs that are "pure" in terms
of being based on some state of "master" is pushing work on reviewers who
want to apply the patches to their own trees.


>
>                      -David
> _______________________________________________
> cfe-dev mailing list
> cfe-dev at lists.llvm.org
> https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20200116/49680d6d/attachment.html>